NAME

SYNOPSIS

DESCRIPTION

The
rand()
function computes a sequence of pseudo-random integers in the range 0 to
{RAND_MAX}
with a period of at least 232.

The
srand()
function uses the argument as a seed for a new sequence of
pseudo-random numbers to be returned by subsequent calls to
rand().
If
srand()
is then called with the same seed value, the sequence of pseudo-random numbers
will be repeated. If
rand()
is called before any calls to
srand()
are made, the same sequence will be generated as when
srand()
is first called with a seed value of 1.

The implementation will behave as if no function defined in this document calls
rand()
or
srand.

The
rand()
interface need not be reentrant.

The
rand_r()
function computes a sequence of pseudo-random integers
in the range 0 to {RAND_MAX}.
(The value of the {RAND_MAX}
macro will be at least 32767.)

If
rand_r()
is called with the same initial value for the object pointed to by
seed
and that object is not modified between successive returns and calls to
rand_r(),
the same sequence shall be generated.

RETURN VALUE

The
rand()
function returns the next pseudo-random number in the sequence. The
srand()
function returns no value.

The
rand_r()
function returns a pseudo-random integer.

ERRORS

No errors are defined.

EXAMPLES

None.

APPLICATION USAGE

The
drand48()
function provides a much more elaborate random number generator.

The following code defines a pair of functions which could
be incorporated into applications wishing to ensure that the
same sequence of numbers is generated across different machines: